1. Field of the Invention
The present invention relates to a mobile communication terminal such as a portable telephone terminal.
2. Description of the Related Art
In the prior art, portable telephone terminals that are connected to a radio communication network and communicate information have included devices that are used by connecting to an external storage device (hereinafter referred to as portable storage device). The portable storage device stores information such as identification information and billing information relating to the user of the portable telephone terminal, which is used to connect the portable telephone terminal to the radio communication network.
Radio communication networks that are used by portable telephone terminals that use a portable storage device include GSM (Global Systems for Mobile communications) or DCS (Digital Communication Services) 1800 which are the digital mobile communication standards in Europe, and PCS (Personal Communications Services) 1900, which is the digital portable telephone standard in North America. In these modes, GSM uses the 800 MHz frequency bandwidth, DCS 1800 uses the 1800 MHz frequency bandwidth, and PCS 1900 uses the 1900 MHz frequency bandwidth.
In these different radio communication networks, communication is performed using substantially the same protocol. Thus, information for setting the communication protocol that relates to the radio communication network used in portable telephone terminals is stored in the portable storage device, and the portable telephone terminal is then connected to the radio communication network. Portable storage devices that are in current use include IC cards such as SIM (Subscriber Identity Module) cards and USIM (Universal Subscriber Identity Module) cards. IC cards such as SIM cards and USIM cards can be inserted into or removed from an interface that is provided in a portable telephone terminal. In addition, services that employ the functions of an SAT (SIM Application Toolkit) or USAT (USIM Application Toolkit) of the 3GPP standard are being developed for portable telephone terminals in which this type of SIM card or USIM card can be installed.
When developing a portable telephone terminal, tests are carried out to determine whether the protocol being used in communication is operating normally. Such tests include, for example, indoor tests for testing a portable telephone terminal inside a room such as a laboratory and field tests for testing a portable telephone terminal outdoors using an actual base station. Field tests are carried out after first determining through indoor tests that a portable telephone terminal operates normally.
In a field test of the communication protocol that is used in portable telephone terminal communication, portable telephone terminal 1103 performs communication such as call origination, connection, and conversation with base station 1101 by way of radio interface 1102 as shown in FIG. 1. At this time, SIM card 1104 is inserted into portable telephone terminal 1103, and communication with base station 1101 is carried out.
Protocol simulation tests or acquisition of internal information relating to the internal operation of portable telephone terminal 1103 in field tests is carried out by software on personal computer 1105 (hereinbelow abbreviated as PC 1105), which is the test equipment. This PC 1105 is further provided with internal information acquisition means 1105a for acquiring internal information of portable telephone terminal 1103 and protocol simulation test means 1105b for performing a protocol simulation test by reproducing the field test based on this internal information.
In a field test, the tester uses PC 1105 to set portable telephone terminal 1103 to the test mode, whereupon communication protocol is transmitted to base station 1101 by way of portable telephone terminal 1103. At this time, SIM card 1104 is installed in portable telephone terminal 1103 to allow communication between portable telephone terminal 1103 and base station 1101.
With the transmission of communication protocol, a communication protocol sequence is generated between portable telephone terminal 1103 and base station 1101 during actual communication. This communication protocol sequence is transmitted to PC 1105 by way of portable telephone terminal 1103. PC 1105 acquires internal information of portable telephone terminal 1103 by means of internal information acquisition means 1105a and stores this communication protocol sequence as internal information in a storage device.
When PC 1105 has completed the storage of the communication protocol sequence, the reproduction test in the field test is carried out. In the reproduction test, a communication protocol sequence that is communicated between portable telephone terminal 1103 and base station 1101 during actual communication as already described is artificially generated on PC 1105.
The protocol reproduction test is performed by protocol simulation test means 1105b of PC 1105, and the actual communication protocol that was communicated between base station 1101 and portable telephone terminal 1103 is reproduced. With this protocol reproduction test on PC 1105, a tester can examine an actual communication protocol sequence and investigate problem points and points for improvement. If the tester discovers a problem point or point for improvement, the tester takes portable telephone terminal 1103 back to the laboratory and modifies or improves the communication protocol.
FIG. 2 shows the internal configuration of portable telephone terminal 1103 of the prior art. In portable telephone terminal 1103 of the prior art, internal CPU 1201 communicates with radio interface 1102 by way of radio unit 1210 and baseband signal processor 1209. Communication is then on CPU 1201 between logical bus 1207 and baseband signal processor 1209 by way of communication protocol stack 1208. In addition, communication protocol stack 1208 and TE (Terminal Equipment) 1203 and 1205 communicate by way of logical bus 1207 inside CPU 1201. Further, TE 1203 and 1205 perform protocol conversion by means of TAF (Terminal Adaptation Functions) 1204 and 1206 to communicate with communication protocol stack 1208.
As shown in FIG. 2, communication is performed between communication protocol stack 1208 and SIM card 1104 that is installed in portable telephone terminal 1103 by way of logical bus 1207. Upon being installed in portable telephone terminal 1103, SIM card 1104 is connected to UIMF (User Identity Module Function) 1202. SIM card 1104 then communicates with logical bus 1207 by way of UIMF 1202 and exchanges subscriber information or user information that is stored in SIM card 1104 with communication protocol stack 1208 or another block.
Logical bus 1207 is also able to communicate with external interface 1211 of portable telephone terminal 1103, whereby SIM card 1104 can receive and store subscriber information or user information from external interface 1211.
When carrying out a field test, portable telephone terminal 1103 also receives instructions relating to the field test from PC 1105 by way of external interface 1211, whereby the start and end of a field test or the acquisition of information on portable telephone terminal 1103 are executed to carry out desired tests. The internal information of portable telephone terminal 1103 is acquired by internal information acquisition means 1105a of PC 1105 and stored in PC 1105. When carrying out a protocol reproduction test, the reproduction test is executed on PC 1105 by means of protocol simulation test means 1105b based on the internal information of portable telephone terminal 1103 that has been stored in PC 1105.
FIG. 3 shows an example of the internal configuration of SIM card 1104. SIM card 1104 includes CPU 1301, internal bus 1306, external interface 1307, and memory 1308. CPU 1301 includes SIM function execution unit 1305. SIM function execution unit 1305 communicates with external interface 1307 by way of internal bus 1306 and transfers subscriber information and user information that have been stored in memory 1308 to portable telephone terminal 1103 based on instructions from portable telephone terminal 1103. SIM function execution unit 1305 further stores data that have been received from portable telephone terminal 1103 in memory 1308.
As previously explained, a field test of the prior art requires dedicated equipment (for example, a personal computer or test software) for acquiring internal information of a portable telephone terminal and for protocol simulation tests. As a result, the field test method of the prior art, while excelling in test flexibility and visibility, has the problems of poor maneuverability and portability. Although test functions can be provided inside the portable telephone terminal (software and hardware), there is a limit on resources such as memory, and as a result, only extremely limited and simple test functions can be realized.
Further, the test equipment that is used in field tests is equipment that the service provider or manufacturer of the terminal uses in the development or maintenance of the terminal and is not made available to general users. As a result, a user is not able to obtain internal information in a real time fashion regarding a problem that occurs when the user is using the portable telephone terminal.
When analyzing a problem, the service provider or manufacturer of a terminal is forced to depend on guesswork or incomplete information from a user regarding the state of use, and a great deal of time and effort is necessary to reproduce a problem and investigate the source of a problem. Thus, problems that occur in a portable telephone terminal cannot be investigated efficiently and problems are difficult to solve quickly, and therefore, portable telephone terminals in which problems have occurred cannot be quickly repaired and returned to the user.